The Trump administration blamed Hamas for the deaths of dozens of Palestinians killed by Israeli soldiers during mass protests along the boundary fence Monday, the deadliest day of violence since the 2014 Israel-Gaza conflict.

The clashes came as a high-level U.S. delegation visited Israel for the inauguration of the new U.S. Embassy in Jerusalem — a break from years of U.S. policy to refrain from establishing an embassy in the contested city until a peace deal was made between the two sides.

“The responsibility for these tragic deaths rests squarely with Hamas,” deputy White House press secretary Raj Shah told reporters at a briefing, referring to the militant group that governs Gaza. “Israel has the right to defend itself.”

The Trump administration’s refusal to admonish Israel for the escalating violence was immediately criticized by Palestinian and human rights groups that said the United States must call on its key ally to exercise restraint amid the escalating chaos and violence.

“The U.S. silence is license to kill for Israel, and Israel is taking this license to heart and implementing it in full,” Husam Zomlot, the top Palestinian representative to the United States, said in an interview with The Washington Post. “The right of people to assemble peacefully has been a founding principle of the U.S. Failing to speak up is a dent in the moral history of this country.”

The United States has consistently backed Israel since violence erupted in Gaza after the Trump administration’s recognition of Jerusalem as Israel’s capital. In April, Secretary of State Mike Pompeo refused to criticize Israel when asked about the 39 Palestinians who were killed that month and the hundreds wounded.

“We do believe the Israelis have the right to defend themselves, and we’re fully supportive of that,” he said.

The approach is rare for U.S. administrations, which in the past have often criticized the Israelis and Palestinians during major flare-ups in violence.

“Normally, you’d criticize protesters rushing the fence, but you’d also hear the U.S. encourage restraint on Israel’s part,” said Ilan Goldenberg, a State Department official in the Obama administration and a fellow at the Center for a New American Security. “That’s how previous administrations would deal with it.”

At the briefing, Shah continued to solely blame Hamas when asked again about the violence and whether the White House thinks Israel should exercise restraint. “We believe that Hamas as an organization is engaged in cynical action that is leading to these deaths,” he said.

Israeli troops fire tear gas at Palestinian protesters Monday during clashes after protests near the border with Israel in the northern Gaza Strip. (Haitham Imad/EPA-EFE/Shutterstock)

The Israeli Foreign Ministry also blamed Hamas, saying the group organized the protest to “sabotage” the Israel-Gaza fence and “storm into Israel.”

“Israel will not allow the infiltration of hostile elements & will protect its citizens from Hamas violence,” the ministry said in a statement.

An estimated 35,000 Palestinians gathered on the edges of Gaza on Monday, fanning out along the fence. Some threw stones, and organizers urged others to burst through the fence. But most of the demonstrators were peaceful.

As gunfire broke through the protests, ambulances roared in and out. More than a thousand protesters were injured, and hospital workers reported being overwhelmed.

Sari Bashi, who focuses on Israeli-Palestinian issues for Human Rights Watch, said the Trump administration is “ giving Israel a green light to continue killing and maiming.”

“Whoever the demonstrators represent — and many of them are young people simply representing themselves and their frustrated dreams — entering a border zone declared off limits by Israel is not a crime punishable by death,” Bashi said.

Later in the White House briefing, Shah was asked when the White House last reached out to Palestinians.

“I don’t honestly have an answer for you,” he said.

Contact between the White House and Palestinians was curtailed in December after Palestinians condemned the Trump administration’s move to recognize Jerusalem as Israel’s capital. Zomlot noted Monday, however, that he remains in touch with the State Department on bilateral issues.

During the White House briefing, a reporter noted that Israeli snipers have killed people who were throwing rocks 50 meters from the wall. Shah responded by saying, “Again, we believe that Hamas is responsible for this.”

Later Monday at the State Department, Pompeo was asked about the violence. The top diplomat turned his back and walked away.

Jenna Johnson in Washington and Loveday Morris and Hazem Balousha in the Gaza Strip contributed to this report.

John Hudson is a national security reporter at The Washington Post covering the State Department and diplomacy. He has reported from a mix of countries including Ukraine, Pakistan, Malaysia, China, and Georgia.